ponymap/plugins/irc.c
Přemysl Janouch eb0f8a028c Implement a Lua 5.3 plugin loader plugin
Also implemented SOCKS detection in said language.

There are probably going to be some bugs.

The program is no longer Valgrind-clean, as that would require plugin
deinitialization, in which there is very little point.
2015-01-18 04:14:45 +01:00

317 lines
7.3 KiB
C

/*
* http.c: IRC service detection plugin
*
* Copyright (c) 2014, Přemysl Janouch <p.janouch@gmail.com>
* All rights reserved.
*
* Permission to use, copy, modify, and/or distribute this software for any
* purpose with or without fee is hereby granted, provided that the above
* copyright notice and this permission notice appear in all copies.
*
* THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
* WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
* MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY
* SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
* WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION
* OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN
* CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
*
*/
#include "../utils.c"
#include "../plugin-api.h"
// --- IRC utilities -----------------------------------------------------------
struct irc_message
{
struct str_map tags; ///< IRC 3.2 message tags
char *prefix; ///< Message prefix
char *command; ///< IRC command
struct str_vector params; ///< Command parameters
};
static void
irc_parse_message_tags (const char *tags, struct str_map *out)
{
struct str_vector v;
str_vector_init (&v);
split_str_ignore_empty (tags, ';', &v);
for (size_t i = 0; i < v.len; i++)
{
char *key = v.vector[i], *equal_sign = strchr (key, '=');
if (equal_sign)
{
*equal_sign = '\0';
str_map_set (out, key, xstrdup (equal_sign + 1));
}
else
str_map_set (out, key, xstrdup (""));
}
str_vector_free (&v);
}
static void
irc_parse_message (struct irc_message *msg, const char *line)
{
str_map_init (&msg->tags);
msg->tags.free = free;
msg->prefix = NULL;
msg->command = NULL;
str_vector_init (&msg->params);
// IRC 3.2 message tags
if (*line == '@')
{
size_t tags_len = strcspn (++line, " ");
char *tags = xstrndup (line, tags_len);
irc_parse_message_tags (tags, &msg->tags);
free (tags);
line += tags_len;
while (*line == ' ')
line++;
}
// Prefix
if (*line == ':')
{
size_t prefix_len = strcspn (++line, " ");
msg->prefix = xstrndup (line, prefix_len);
line += prefix_len;
}
// Command name
{
while (*line == ' ')
line++;
size_t cmd_len = strcspn (line, " ");
msg->command = xstrndup (line, cmd_len);
line += cmd_len;
}
// Arguments
while (true)
{
while (*line == ' ')
line++;
if (*line == ':')
{
str_vector_add (&msg->params, ++line);
break;
}
size_t param_len = strcspn (line, " ");
if (!param_len)
break;
str_vector_add_owned (&msg->params, xstrndup (line, param_len));
line += param_len;
}
}
static void
irc_free_message (struct irc_message *msg)
{
str_map_free (&msg->tags);
free (msg->prefix);
free (msg->command);
str_vector_free (&msg->params);
}
static void
irc_process_buffer (struct str *buf,
void (*callback)(const struct irc_message *, const char *, void *),
void *user_data)
{
char *start = buf->str, *end = start + buf->len;
for (char *p = start; p + 1 < end; p++)
{
// Split the input on newlines
if (p[0] != '\r' || p[1] != '\n')
continue;
*p = 0;
struct irc_message msg;
irc_parse_message (&msg, start);
callback (&msg, start, user_data);
irc_free_message (&msg);
start = p + 2;
}
// XXX: we might want to just advance some kind of an offset to avoid
// moving memory around unnecessarily.
str_remove_slice (buf, 0, start - buf->str);
}
static int
irc_tolower (int c)
{
if (c == '[') return '{';
if (c == ']') return '}';
if (c == '\\') return '|';
if (c == '~') return '^';
return c >= 'A' && c <= 'Z' ? c + ('a' - 'A') : c;
}
static size_t
irc_strxfrm (char *dest, const char *src, size_t n)
{
size_t len = strlen (src);
while (n-- && (*dest++ = irc_tolower (*src++)))
;
return len;
}
static int
irc_strcmp (const char *a, const char *b)
{
int x;
while (*a || *b)
if ((x = irc_tolower (*a++) - irc_tolower (*b++)))
return x;
return 0;
}
static int
irc_fnmatch (const char *pattern, const char *string)
{
size_t pattern_size = strlen (pattern) + 1;
size_t string_size = strlen (string) + 1;
char x_pattern[pattern_size], x_string[string_size];
irc_strxfrm (x_pattern, pattern, pattern_size);
irc_strxfrm (x_string, string, string_size);
return fnmatch (x_pattern, x_string, 0);
}
// --- Other selected IRC stuff ------------------------------------------------
#define IRC_MAX_NICKNAME 9 ///< The limit from RFC 2812
#define IRC_RPL_WELCOME 1
#define IRC_RPL_MYINFO 4
// --- Service detection -------------------------------------------------------
static struct plugin_data
{
void *ctx; ///< Application context
struct plugin_api *api; ///< Plugin API vtable
}
g_data;
struct scan_data
{
struct str input; ///< Input buffer
struct unit *u; ///< Scan unit
};
static void *
scan_init (struct service *service, struct unit *u)
{
(void) service;
char nick[IRC_MAX_NICKNAME + 1];
size_t i;
for (i = 0; i < sizeof nick - 1; i++)
nick[i] = 'a' + rand () % ('z' - 'a' + 1);
nick[i] = '\0';
struct str hello;
str_init (&hello);
str_append_printf (&hello,
"NICK %s\r\nUSER %s 8 * :%s\r\n", nick, nick, nick);
g_data.api->unit_write (u, hello.str, hello.len);
str_free (&hello);
struct scan_data *scan = xcalloc (1, sizeof *scan);
str_init (&scan->input);
scan->u = u;
return scan;
}
static void
scan_free (void *handle)
{
struct scan_data *scan = handle;
str_free (&scan->input);
free (scan);
}
static void
on_irc_message (const struct irc_message *msg, const char *raw, void *user_data)
{
(void) raw;
struct scan_data *scan = user_data;
unsigned long code;
if (!irc_strcmp (msg->command, "PING"))
{
// Without this we might be unable to finish registration
struct str pong;
str_init (&pong);
str_append_printf (&pong, "PONG :%s\r\n",
msg->params.len > 0 ? msg->params.vector[0] : "");
g_data.api->unit_write (scan->u, pong.str, pong.len);
}
else if (strlen (msg->command) == 3 && xstrtoul (&code, msg->command, 10))
{
// It looks like we've successfully registered
if (msg->prefix && code == IRC_RPL_WELCOME)
g_data.api->unit_set_success (scan->u, true);
// Extract the server name at least
if (code == IRC_RPL_MYINFO && msg->params.len > 0)
{
char *info = xstrdup_printf ("%s: %s",
"server name", msg->params.vector[1]);
g_data.api->unit_add_info (scan->u, info);
free (info);
g_data.api->unit_abort (scan->u);
}
}
}
static void
on_data (void *handle, const void *data, size_t len)
{
struct scan_data *scan = handle;
str_append_data (&scan->input, data, len);
irc_process_buffer (&scan->input, on_irc_message, scan);
}
static struct service g_irc_service =
{
.name = "IRC",
.flags = SERVICE_SUPPORTS_TLS,
.scan_init = scan_init,
.scan_free = scan_free,
.on_data = on_data,
.on_eof = NULL,
.on_error = NULL,
.on_aborted = NULL
};
static bool
initialize (void *ctx, struct plugin_api *api)
{
g_data = (struct plugin_data) { .ctx = ctx, .api = api };
api->register_service (ctx, &g_irc_service);
return true;
}
struct plugin_info ponymap_plugin_info =
{
.api_version = API_VERSION,
.initialize = initialize
};